Regarding the UWB-IR system, JP-A No. 241860/2004 and JP-A No. 241859/2004 disclose a pulse generator that is configured to obtain a pulse signal for transmission by synthesizing a mixer output of a signal of a local oscillator and a Gaussian pulse using the local oscillator and the mixer. Moreover, JP-A No. 241860/2004 also discloses a technique of generating a pulse shaped signal of a low frequency by assigning weights to output signals of a plurality of current sources.
Moreover, JP-A No. 535552/2003 discloses a transmitter that transmits information in a series of impulse waveforms and controls a form of the each impulse. FIG. 26 and FIG. 28 of JP-A No. 535552/2003 disclose a wavelet generation circuit that generates a square wave pulse whose pulse width is narrow from a differential delay using a plurality of lines each giving a different delay effect in order to generate a plurality of impulses.